Dryer hood construction for web material



Jan. 26, 1965 E. J. JUSTUS ETAL 3,167,408

DRYER HOOD CONSTRUCTION FOR WEB MATERIAL Filed Nov. 16, 1961 s Sheets-Sheet 1 INVENTORJ faivar 11 711.; {as

A TTORNE YS DRYER HOOD CONSTRUCTION FOR WEB MATERIAL Filed Nov. 16, 1961 8 Sheets-Sheet 2 4 /J2 12 1 I I '3 i 4 5 g i2 INVENTORS fafyar' JJas Laa W Bylaurregzce ,floor'e A TTORNEYS Jan. 26, 1965 E. J. JUSTUS ETAL 3,167,408

DRYER HOOD CONSTRUCTION FOR WEB MATERIAL Filed Nov. 16, 1961 8 Sheets-Sheet 3 W6 F; W MW M3 y 5 M i| M I l l I l l I IN VEN TORS [dyar J J11; 71-5 Bylazzfr'entefi Woo/ e A TTORNE YS Jan. 26, 1965 E. J. JUSTUS ETAL 3,157,408

DRYER HOOD CONSTRUCTIQN FOR WEB MATERIAL Filed NOV. 16, 1961 8 Sheets-Sheet 4 Q? INVENTORS [dyer J J'usfils BY laa/rewcefl floor-e ATTORNEYS Jan. 26, 1965 E. J. JUSTUS ETAL 3,167,408

DRYER HOOD CONSTRUCTION FOR WEB MATERIAL Filed Nov. 16, 1961 8 Sheets-Sheet s fig. 8

97 I w "I l 103 g l I l l INVENTORS [:{yar J'J'lzsfzzs BYZmv ren aejZ Woare A TTORNE YS 1965 E. J. JUSTUS ETAL 3,

DRYER HOOD CONSTRUCTION FOR WEB MATERIAL Filed NOV. 16, 1961 8 Sheets-Sheet 6 INVENTORS L a 7a?" J Jms {as BYlawerzae/Z. #002 6 W 42 MM 2 W A TTORNEYS Jan. 26, 1965 E. J. JusTus ETAL 3,167,408

DRYER HOOD CONSTRUCTION FOR WEB MATERIAL Filed Nov. 16, 1961 a Sheets-Sheet 7 INVENTORJ (f [dyar fJksZaa fin BY Lzzgpezzcezi, Moore 9 M A TTORNE YS Jan. 26, 1965 E. J. JUSTUS ETAL DRYER HOOD CONSTRUCTION FOR was MATERIAL 8 Sheets-Sheet 8 Filed Nov. 16, 1961 e i 1 wffl 0 11% ra W 3 M United States Patent 3,167,403 DRYER H001) CONSTRUCTIGN FUR WEB MATERIAL Edgar J. Justus and Lawrence A. Moore, Eeloit, Win,

assignors to Beloit Corporation, a corporation of Wiscousin Filed Nov. 16, 1961, Ser. No. 152,836 7 Claims. (Cl. 34122) This invention relates to improvements in dryers for I fibrous materials and more particularly relates to an improved torm of drier for use in the making of paper.

, A principal object of the invention is to provide an improved drier for use in the making of paper arranged with a view toward more uniformly removing moisture throughout the width of a traveling fibrous web.

Another and important object of the invention is to provide an improved form of drier for drying continuously traveling webs of fibrous material, in which the speed and uniformity of moisture removal is increased by varying the application of heat throughout the width of the traveling web and confining the heated air for application to the web, to be discharged through a plurality of adjacent plenum chambers extending helically along the web.

A further object of the invention is to provide a simple and improved form of drier for use in the making of paper, so arranged as to be capable of being used in various positions relative to a surface to be dried.

Still another object of the invention is to provide a simplified and improved form of drier hood for drying traveling webs of fibrous material having a simple and improved power operated mechanism for removing the hood from the traveling web and retaining the hood in fixed relation with respect to the traveling web.

A further object of the invention is to provide an improved drier hood construction for traveling webs of fibrous material, in which the air circulation ducts for the drier hoods for use in the making of paper for drying traveling fibrous webs, in which heated air is distributed along the surface of the web by independent operation of a series of air distribution valves distributing the air to plenum chambers extending along and across the webs, and in which the side walls of the plenum chambers are in the form of helical baffles to enhance the uniformity in drying of the web along adjacent ends of the plenum chambers.

These and other objects of the invention will appear from time to time as the following specification proceeds and with reference to the accompanying drawings wherein:

FIGURE 1 is a diagrammatic perspective view of a drier hood constructed in accordance with the invention 3,167,468 Patented Jan. 26, 1965 "ice looking towards the rear end portion of the hood in order to show the inlet and outlet ducts;

FIGURE 2 is a transverse sectional view taken through the drier hood substantially along line II--II of FIG- URE 1;

FIGURE 3 is a perspective view of the plenum chamber, showing the valves for varying the flow of air into the plenum chamber, the impingement nozzles for impinging air on the traveling web and the exhaust passageways for drawing spent air from the web;

FIGURE 4 is a fragmentary side view of the drier shown in FIGURE 1 with certain parts broken away and certain other parts shown in vertical longitudinal section;

FIGURE 5 is a plan view of a plate from which the helical baflles are made, showing the layout of the batlies on the plate for cutting the ballies from the plate with a minimum of waste;

FIGURE 6 is a fragmentary detail plan view showing a form of damper valve that may be used to control the flow of air to the plenum chambers;

FIGURE 7 is a fragmentary plan view of the circulating air fans and damper therefor, with certain of the ducts shown in horizontal section;

FIGURE 8 is an enlarged fragmentary detail front end view of a portion of the hood shown in FIGURE 1, showing the mechanism for raising and lowering the hood with respect to the traveling web;

FIGURE 9 is a diagrammatic view diagrammatically illustrating the air flow through the apparatus;

FIGURE 10 is a moisture content graph comparing the removal of moisture by the use of helical bafiles in contrast to parallel bafiles in alignment with the line of travel of the web along the hood; and

FIGURES l1, 12, 13, 14, 15, 16 and 17 are diagrammatic views illustrating various ways in which the hood can be installed with respect to the drier surface and various means for moving the hood toward and from the drier surface.

In the embodiment of the invention illustrated in the drawings, in FIGURES 1 and 2 a drier hood 10 is shown as comprising a top wall 11, side walls 12 and a rear end wall 13 having an air inlet 16 leading thereinto and an exhaust outlet 17 leading therefrom. 'The hood also has a front wall (not shown) similar to the rear wall 13 and having access openings (not shown) leading into said hood.

The top wall, side walls and end walls of the hood 10 may be made from a suitable insulating material carried in a metal frame structure, a portion of which is shown herein and indicated generally by reference character 18.

The hood 10 also has a semi-cylindrical bottom wall in the form of an impingement plate 19 conforming generally to the form of the Web as it passes about a rotating drying cylinder 20. The impingement plate 19 forms the bottom plate of a series of plenum chambers 21 arranged in side by side relation with respect to each other for the full length of the hood 10 and drying cylinder 20, and having a series of air impingement nozzles or orifices 23 leading therethrough for impinging heated air onto a fibrous web 22 traveling about the drying cylinder 20. The impingement plate 19 also has exhaust passageways 24 leading therethrough withdrawing moist air from the web traveling about the drying cylinder for exhaust totheatm'osphere through the exhaust pas-' sageway 17, or for'heating and recirculation through the air impingement nozzles 23. I

The plenum chambers 21 are generally cresent-shaped in transverse vertical section and are formed from the lower impingement plate 19, an :upwardly spaced semitions thereof and are suitably secured thereto, asby weldplates into theplenum r the plate 19, but 7 is spaced vertically of the plate 19 and has a longercir-f cumferential surface than the plate 19,.opposite ends of f which abut; the plate "19 at the opposite lower end por- 73, 7,40 f V r I of the top wall 11 Within a sleeve'47 rotatablymounted r in a horizontally extending channel 49 extending for the length of the hood11 and forming a partition-within said hood. 'Thejpiston' rod-43 isconnected'with the shaft'45 through iailink 50 pivotally connected at the end of said pistonrod,'and a, crank 51 extending from the rod 45.

The connection from the sleevex47 to the rotatable valve plate 37 includes a gearsector 53. on the lower end of vthe sleeve 47 and a gear sector '54 fixed to the movable valve plate; 37 and meshed with the gear sector 53.

The damper .valves33 may thus be individually fully or partially openedor closed to determine the amount ing. End walls2 7 close opposite endso'fthe plates 19 and 25.

The batlles 26 ,are shown 'inFIGURlE as being laid? inner margin 29 conforming to the contour of'th'e inner inner-margin 29 a distance equal to the spacing between the inner sides of the plates 19' and 25.] The bafiies 26 may thus-bercut from plate material with a minimum of waste of material. v if The baffies 26 being cut to' the formshownin VFIG- URI: '5 are helically mounted in ,the space betweenthe. plates 19 and in equally spaced relation with respect, to eachother and at the same pitch, to 'form the plenum.

,out on a'strip of plate material. Each bafile' 26.has ane 2O ,margin of the plate 19 and an outer margin 30 of the j same radius asrthe inner margin 29, but spaced from the of air to be admitted toeach individual plenum chamber, ''and to thereby control themoisture profile of the web of fibrousumaterial*beingdried,"as will hereinafterr be more iclearly described-as this specification proceeds;

The space 'above the plate '25 is divided into a presr sure'zone Aim-communication withthe air valves 33 and air iulets31, and a vacuum zone B in communica- 'tion with the, exhaust pipes 24,,and intakes 55. of indi vidual air fans. 56, 'for each plenum chamber 21'. vThe 'zones A and B1 extend forv the entirellength' of the hood' ijlo'between thelend walls thereof.-

chambers 21 in. communiction with'the web itraveling' The plate 2 5 has a plurality of airjinlet s :31. leading i thereinto through. the topthereof Each air inlet leads ,about the drying-cylinder 20 through the impingement to an individual plenum chamber'zl and .has 'an fout-r '1:

wardly fiaredupstream end 32' having an air damper valve 33 at the inlet. end thereof, controlling the flow of -air intothe individual plenum chambers in'acco'rda'nce with therequirements for uniformly dryingthe traveling 7 web.

A preferred forrnof air damper valve 33 is shown FIGURE 6 as including an elongated stationary" plate '35 mounted in the outwardly,flaredupstream end 32 of a w an: associated airi-nlet 31 and having a plurality of sa mental air openings 36 and 36a of different areas lead ing therethrough. A vertical pivot'pin37 extends up} wardly of the center'ofthe stationary valve plate and forms a pivotal mounting for a rotatable valve plate 39 having segmental openingsi40 and 40a, correspondingito the segmental openings 36 and 36aleading throughhthe stationary plate35; Y

I 7 Each air valve orfdainper'33is operated arr-in-v dividual= air motor dlp The [air motors 4lf arefmounted" on the top of the top'wall 11 of the-hood 10-and"are "pingernentnozzles or orifices 23.

The zones AnandB are separated, by twojchannel-like partitions 57 and'59 arranged in abutting engagement with I each other and abutting'one sidewall '12 of thehood and suitablyisecured to the supporting frame work.18

therefoni .The partition .57' forms-a mounting for a heater.

' 'nnit60' e'xtendingtor the lengthof the hood 10. The

' adjacent partition 59 has the air :inlets3 1 leading. therethrough and suitably sealedathereto, andjforms' a support for; said air iinlets; A vertical" par'tition'61' is secured to r and extends upwardlyofan Iupwardlyfacirig flanged portion 62' of the inner partition' 59,:and'extends upwardly gof ;said?'fianged;portion angularly inwardly to the chairriel-like partition 49 and upwardly therefrom for the length ofthe ho'od '10; *The par titions 5'l," 59 and :61 'to- 'gether with thefhousing 63 for the'air fan 56 thuslsepa rate the chambers and B fromjeach otherran'd accom modate the circl latien of air. through the exhaust. pipes, 2ft and. fan 56: tothe pressure chamber-A through the heaters 60 andairgvalves 33 into the plenum chambers 21, andfout'the plenum chambers 21 through the im- 1 Thedan 56' may be a 'well known formiof suction *hlowerfland is shown in "FIGURE 2' as being mounted 1 "en the lower end-of. avertical motor shaft, 65, depending from .a motor 66 mounted 'on'jand extending upwardly ofthe topwall not the hood 10. The fan housing:63 iswshownin IGU E} asbeing in the form of a'scroll'having the intake opening through the bottom thereot and, extending upw ar'dly to said fan The fan operative to 'openor close each air valve {33 in accordance" with the requirementfor' air in each plenum chamber 21 Each air motor-41 may generally comprise a' piston rod I to completely close the associated airvalve 'upon the V accommodate the air valve to be partially or-run opened,

dependent upon the pressure of airjadmitted to the head, end of the cylinder 44. A specific setting ofeach valve may, therefore, be attained for each selected increment of air pressure.

The operative connection from each piston'r'od" 43 to 7 housing: 63has anoutlet 67,in; communication witha diverglng duct 69; leading through a vertical'wallportion'701of the par'titionffil and shown ,asthaving' outer parallel, wallportions-72Iterminatingin a partition 73 extending vcrticallyofrthe channeled, partition 49 to the top, ofi 'the' hood '10... The'parallel wall portions" 72 of 3 retractiblimQVed WithresPect to a cyli nder' 44 jbyr aj. the duct have Yasefiss P v 7 extend spring (not shown) and ,extensibly moved with respect to said cylinder by a piston or'diaphragm- (not shown), operatively connected with said piston rod, upon the ad-" ing therein; {The damping louvers '75.,ha'verpivot pins mounted in lugs 76. The lugs .76 project outwardly of release of air underpressure-from; the cylinder 44 and to the. partition'73 adjacent the parallel wall portions 72.

The dampers 75 have a greater portion'of their weight outwardly of the pivotpins. 77 so that the air flow through ttheductp69 forces the dampers, into the openposition each air valve 33 includes a vertical shatt or rod; 45 rolyr of the top wall 11 I The rod 45 extends downwardly tatably mounted in a bearing boss 46 projecting upward shown in--FIGURE 7'. When, however, an individual fan a 56 is' 'shut off, the fdampers will close and prevent the short cireuitingflof air through the fan not in' operation.

A filter 78 extends for the entire ,length of zone B beneath the intake 55 ofv the fan 5 6, to filter paper, dust monly known as moisture profile curves.

The heating element 60 extends for the full length of the hood and may be in the form of high pressure steam coils for raising the temperature of the air to be impinged on the traveling web to the required degree.

The air inlet 16 leading into zone B has a damper 79 therein diagrammatically shown in FIGURE 9. The exhaust outlet 17 in a like manner has a damper 80 therein.

The dampers 79 and 80 may be independently opera-ted and are provided to accommodate the recirculation of air through the system and to mix fresh air with the circulating air, to reduce the moisture content of the air.

During normal operation of the drier the damper 79 may be open to the extent required to maintain the circulating air at the proper moisture content. The fans 56 will then draw air into zone B through the inlet 16 under the control of the damper 79 and will draw in exhaust air through the exhaust passageways 24 through the filter 78, to filter paper fiber and debris therefrom,

andforce the air through the damping louvers 75 into the pressure chamber A. The air will then be forced through the heater coils 60 and through the individual air valves into the plenum chambers 21 from which the air is forced at high velocity through the impingement nozzles 23 onto the traveling fibrous web. The air having performed its function on the fibrous web is then drawn back into zone B through the exhaust passageways 24, where it may be mixed with fresh air to maintain the air at the required moisture content and recirculated through the air filter 78.

It may here be seen that by regulating the damper 79, the moisture content of the circulating air may be regulated and that by regulating the air damper valves 33 the distribution of hot air over the surface of the web may also be regulated.

In FIGURE 10, we have shown graphic plots of the percentage of water content in the fibrous web at increments of width across the web. Such plots are com- Curve C is a curve showing the moisture profile across a fibrous web that may be attained with no correction for moisture content, in the web throughout the width of the web. Curve D is a corrected moisture profile curve that may be attained by controlling the air damper valves 33 in accordance with the requirement for removal of moisture from the web across the entire width thereof. This curve shows a relative uniform moisture profile across the width of the web with hatched peaked portions E. These hatched portions E are attained by the use of straight bafiles extending in the direction of travel of the web and forming the side walls of the plenum chambers.

Where the bafiles are helically mounted in the plenum as in the present invention, the distribution of air from the individual plenum chambers and the resultant drying effect is blended along the adjacent sides of each plenum chamber, resulting in the removal of the peaked hatched portions E from the curve and a relatively level and smooth moisture profile across the width of the web.

Referring now in particular to FIGURES 4 and 8 illustrating a form of mechanism that may be utilized for lifting the hood 11) as a unit from the drying cylinder 20 to afford access to said cylinder for threading a web over said cylinder, or for removing a broken web from said cylinder, a fluid operated motor 83 is shown as being mounted on a transversely extending beam 90 of a frame structure 84 for the drying cylinder 20. The motor 83 drives an aligned shaft 85 through a coupling 86. The shaft 85 is journalled in and extends within a mitre gear box 87 and drives transverse shafts 88 through mitre gears (not shown) contained Within said mitre gear box. The shafts 88 extend outwardly from opposite sides of the mitre gear box 87 and drive lifting jacks 89, mounted on the cross beam 90 of the frame structure 84 adjacent opposite ends of said cross beam. The drive from each shaft 88 to the associated jack 89 comprises spaced couplings 91, one of which is driven from the shaft 88 and the other of which drives a shaft 93, for driving the lifting jack 89, and a coupling shaft connecting the couplings 91 together.

The lifting jacks 89 may be well known forms of screw jacks and each has a depending threaded shaft 96 having a coupling member 97 on its lower end extending through a top plate 99 of a bracket 100. A collar 101 on the coupling member 97 abuts the bottom of the plate 99. Lock nuts 103 threaded on said coupling retain said collar to the underside of the plate 99. Operation of the air motor 83 will thus raise or lower the front end of the hood 10 with respect to the frame structure rotatably supporting the drum 20.

The rear end of the hood 18 is raised simultaneously with the front end of said hood by chains 105 extending along opposite sides of said hood. The front ends of the chains 185 have connectors 106 thereon connected to brackets 107 connected to the frame structure 84 supporting the drying cylinder 20. The chains 105 extend upwardly of the brackets 107 around idler sprockets 109 suitably journalled on the drier hood 1t) and along opposite side walls 12 of the hood 10 under idler sprockets 110 mounted on brackets 111 on pivot pins 112. The brackets 111 are mounted on the rear Wall of the drier hood 1!) and frame structure 12 therefor and project rearwardly therefrom. The chains 105 are trained under the idlers 110 and upwardly therefrom and have connectors 112 pivotally connected to their upper ends. The con nectors 112 extend through and are connected to brackets 113, mounted on the frame structure 84, supporting the drying cylinder 20. Thus, as the front of the hood is raised, the chains 185 being connected to the frame structure 84 for the drying cylinder 20 at their opposite ends and being trained over and under the respective sprockets 109 will lift the rear end portion of the hood with the front end portion thereof and raise the air impingement plate 19 about the drying cylinder 20.

In FIGURES 11 through 17 we have diagrammatically shown various alternate ways in which the hood 10 may be lifted above the drying cylinder 20 and various positions in which the hood 10 may be installed about the periphery of said dryer drum. In FIGURES 11 and 12 the hood 10 has stops 115 projecting forwardly of its front wall adapted to rest on adjustable stops 115a on the supporting frame structure for the dryer drum 20. The hood 10 also has two spaced bars 116 spaced above the stops 115 to which may be attached lifting chains by way of clevices and the like (not shown) for lifting the hood 18 about the axis of a pivot pin 117 spaced rearwardly of the rear wall thereof. The pivot pin 117 pivotally supports an arm 118 extending rearwardly of the rear wall of the hood 10, on a bracket 119 mounted on the supporting frame work for the drying cylinder 20.

In FIGURES 13 and 14 we have shown a hoist unit 121 mounted on top of the hood 10 and have shown flexible cables 122 and 123 extending in opposite directions from said hoist unit. Both cables 122 and 123 are wound in upon operation of said hoist unit. The flexible cable 122 is trained over a sheave 124 mounted at the front end of the hood 1%) and is trained downwardly from the sheave 124 to and around a sheave 125 rotatable about an axis perpendicular to the axis of rotation of the sheave 124. From thence the cable 122 is trained upwardly to a fixed abutment 126 which may be the frame structure supporting the drying cylinder 20.

The other flexible cable 123 is trained in a similar manner, but rearwardly of the hoist unit 121 over a sheave 127 at the rear of the hood 1% and downwardly along the rear of the hood around a sheave 129 and upwardly therefrom to a fixed abutment 138 on the frame structure supporting the drying cylinder 28. Guide rails 131 may be positioned at the front and rear of the hood and extend vertically thereof. The guide rails 131 may be engaged by rollers 133 mounted on the front and rear walls of the take with respect to the-drying cylinder 20. I I V i that a simplified I form of self-contained universal dryer'hood has been pro- .vided containing the pressure and suction circulating-pas 1 as it is vertically moved of the hood with respect to said drying cylinder. t

InFIGURE 15 we have shown the hood 10 mounted on flanged wheels 136 riding along rails 137. An adjustable stop 13 9 is provided tolirnit movement of the hood 1 In FIGURE 16, the hood ltl'isvsho'w'n asextending along the underside of the drying cylinder 20 and as being 7 it with respect to the periphery of the drum 26 by engage- V ment with a fixed abutment 140 which may be on the frame structure supporting the drying cylinder -29.

lowered with respect to saiddrying' cylinder 'to'accommodate'the training of a fresh web therearound, or the :removalof a broken'web therefrom. In this, arrangement, the hoodis guided for vertical movement along,

guide rails {143, extending vertically along opposite iends of sai d hood,-on rollers 144, mounted on; the front and,-

rear walls o f-said hood and having rolling engagement with the, guiderails 143. A, flexible cable 145is coni nected at one end to a fixedabutment 146 on the, frame 'structure rotatably supportingthedryingcylinder 20 and;

extends downwardly therefromto andaround; asheave 25' cable extends "upwardly to and around a sheave 149 mounted on a fixedabutrnent 159supported on the sup! porting frame structure for the drying, cylinder 20; From thencethefiexible cable 145 extends downwardly tonand around a sheave 151 and outwardly therefromunder a 147 mounted {on the'hood 10. From thence the flexible .of air including the recirculation of the air without blend- 7 ing and the circulation of air from outside of thehood may be attained and controlled in a simple and efficient a n j Y f While ;we haveherein shown" and described several forms in 'whicho'ur invention may be embodied, it may readily beun'derst ood that various modifications and variations in the invention maybe attained without departing from thesspirit and scopeof-Ithe novel concepts thereof,

g (g) exhaus t passageways-leading from the traveling tension idler-"152w a hoist 153. The 'h oist 153 also has :i

a flexible cable 155' wound thereon, trained in a suitable manner to the rear'end wall of the hood 10,: for lifting said ,hood in the same manner the forward endportion of said f hood isliftecl. rThe take up sheave 152may serve as a is located with respect to the cylinder 20 by. adjustable stops 157 engaging fixed abutments 9' fixed to thesup porting frame structure for the drying cylinder In FIGURE 17, the hood ltlis shown as having a lever 'arni16tl extending from a side wall thereof and pivotally mounted on a stationary bracket 161 on a pivot pin 162. An adjustable stop 163'is adapted to 'abuta fixed abut-v nient .165, 'whichxmay be. a part'of th'e supporting frame .*(f) 'a'plenurrr in communication 1 take up for the two-flexible cables lfand 155 and is 3 7 diagrammatically shown in-FIGURE 15 as beingio'pe-r-f;

ated by a hydraulic cylinderand piston I156. The hood as defined by theclairns appended hereto;

We'claim as our invention: Y

a traveling fibrous web in the making of paper;

g (a) ah'ood, l V (b) apressure zonewi-thin said hood,

j (c) ya vacuum zone within saidhood, g (d): atleast one air fan in lsaid hoodest-abli-shing said pressure: and'vacuumzones, v 1 (e) 'anair heater insaid pressurezone,

' th said pressure zone having a plurality of air impingement nozzles leading therefrom, I

"' web' and passingf-through said plenum andhaving I communication with said vacuum zone, 7 v e (h) and spaced helical, bafilesyextending 'along said plenum and dividing jsaid plenum into a plurality of plenum-chambers having helical siderwalls blending I the air passing thnough'adjacent plenurn'chambers onto'j the traveling web. a i

i i 2. .In a"drying aparatusfand in combination with a dr'yin'g cylinder adapted to'jhavea fibrous we'b trained th r ab t;

(a) a hood extending along said drying cylinder,

(b) a pressure 'z'one withins'aidhood,

structure for the drying cylinder 20. {The hood 10is- {raised and lowered with respect to the drying cylinder. 2E3v l by a flexible cabletiofi which may be trained fromia hoist not shown and is trained upwardlyaround a sheave 1 67, which maybe mounted on thefjsupporting frame struc ture for the drying cylinder 20. l ronrthence, the cable 167 is trained downwardly-t0 and around a sheavef169 ,mounted on the front Wall of the hood 10 and upwardly therefrom to the fixed abutment 165,, to. which its 'is I attached. J a f s t I The foregoing illustrates a gfewof the manywaysin I which the hood 10 may be mounted and withdrawntfr om V and movedinto place with respect tothe drying cylinder 20 and the fibrous web trained thereaboutf and further :illustrates the versatility of the self oontainer dryer hood of the invention and the unlimited positions whichittnay It may be seen from the foregoing,

sageways Within 'the'hood, together with air distributing the distribution of air along the web .to providear'ela tively uniform moisture removal from the Web throughout the width thereof. I t s I a It may still further be seen that by dividing the plenum into a plurality of individual plenum chambers arranged side by side, "by 'thefhelical'baffies Zhthat the airflow (c) a 'vacuum zone, within said hood,

7 7 zones, i; V p I 7 (e) an air filter insaid vacuum zone, ,(;f) an air heater in, sai-d pressure zone, i(gi)' a'plurality of pressure passageways communicat- .ing with said pressure zone and spaced along and with- *in ho d, i; I L

" (h a;plurali-ty of plenum chambers extending along w ys, f r f(i) an air impingement plate forming an outer wall of aid plenum c'hamber s'and con-forming toand spaced I lpsfelyadjacent saiddryingjcylin'der'and'having s (j) a plurality of air impingement no zzles leading 'therethrough; l ,7 1 p i (7c) exhaust passageways pas'sing through said" air impingement plate and affording communication bei tween the, traveling web and said vacuum ,zone, I t for withdrawing spent air from the traveling web,

7(1) and a plurality of spaced helical bafiles extending alongithe inner side of said impingement plate in the direction of travel of the web and defining the side "walls of said plenum chambers.

3. In (a drying apparatus for paper and the like an in combination with 'a'rotating to have a web tr-ainedith ereabout; 7 I

(a): a hood extending'along said cylinder and having a (by an "air impingement plategenerally conformingto I 1.' Inan apparatus particularly adapted for drying a said hood in commnnication withf'said pressure pasdrying cylinder adapted h (c) a pressure zone in said hood, (d) .a vacuum zone in said hood, (2) a plurality of independently operable fans spaced along said hood and common partition means coop- =drawing spent drying air from the traveling web.

10 (g) a pressure zone within said hood having communication with said exhaust outlet, (h) a vacuum zone within said hood having communication with said air inlet,

erating therewith to establish said pressure and vac- 5 (i) a plurality of exhaust passageways passingthrough uum zones, said impingement plate into said vacuum zone, (f) an air heater extending along said pressure zone, (j) a plurality of fans extending along said hood and (g) -a plate spaced from said impingement plate and partition means cooperating therewith to establish sealed thereto, said pressure and vacuum zones, (h) a plurality of helical bafiies in the space between 1 (k) an air heater in said pressure zone downstream said plates, extending in the general direction of travel of said exhaust outlet, of the web along said cylinder and dividing the space (I) a plurality of plenum chambers extending along between said plates into said impingement plate on the inside thereof and (i) a plurality of plenum chambers arranged in side having by side relation with respect to each other, (m) opposite helical side walls extending in the gen- (j) individual air inlets, leading from said pressure eral direction of rotation of said drying cylinder,

zone to said plenum chambers, (n) individual air inlets into each plenum chamber, (k) aplurality of exhaust passageways leading through (0) individual air valves controlling the flow of air said plate and establishing communication between through Said inlets to said Plenum chambers, the web and said vacuum zone, (p) and individually operated air motors having con- (l) independently operable air valves in said inlet int-o n n With a d air Va v s f r determining the posisaid plenum chambers for varying the delivery of air iiOnS 0f a d valvesthereto, 6. In a drying apparatus and in combination with a (m) and dampers at the discharge end of each of said rotatable drying cylinder having a web traveling therefans preventing the short circuiting of air through an about; inoperative fan. (a) a hood extending along said cylinder and having 4. In a drying apparatus particularly adapted for dry- (b) an impingement plate conforming to and spaced s p p Webs and in combination with a drying cylinder; closely adjacent said drying cylinder having (a) extending along Said drying cylinder and (c) a plurality of air impingement nozzles leading having therethrough I n o (b) an air impingement plate generally conformmgto (d) an air inlet leading into said hood,

at: path of travel of the paper web about said cylin- (e) an exhaust outle't q i w Said hoot? (C) apressure lune Within Said hood, (1) damper means 1n sald arr inlet and sald exhaust (d) a vacuum Zone within said hood outlet operable to vary the flow of air into and from (e) at least one fan and common partition means 00- Sald hood operating therewith to establish said pressure and a P f Z0136 wlthm Sald hood havmg commu' vacuum Zones, nrcatron with said exhaust outlet, (f) an i heater in said pressure Zone, (h) a vacuum zone within said hood having commu- (g) an air inlet into said vacuum zone, 40 nice/[i011 with Said air inlet, (h) damper means in association with said air inlet to a plurality of exhaust passageways Passing through vary the flow of air into said vacuum zone, said impingement plate into said vacuum zone, (1) an air outlet from said pressure zone, (j) a plurality of fans extending along said hood and (j) damper means in said air outlet adapted to vary partition means cooperating therewith to establish the flow of air from said pressure zone, said pressure and vacuum zones, (k) a plurality ot helical battles extending along the (k) an air heater in said pressure zone downstream of inner side of said impingement plate in the dlrection id e hau t outlet, travel of the Y Sald cyhndel'g (l) a plurality of plenum chambers extending along a plate extending along t u r p r p y of Said said impingement plate on the inside thereof and bafiles and cooperating with said impingement plate having (mi i i iir aili tg c it 'lenum chambers arran ed 'n side (m) opl-msit-e helical Side walls extending in the by side relation v vith respect to each other having d-lriacnon 9f fotafiqn of said drying cylinder helical Side Walls, (n) nd v dual arr inlets into each plenum chamber, ('11) an ind-ivid ualinlet from said pressure zone into (a) mdlvldurfll valves.contwumg the flow of air each plenum Chamber, through said inlets to said plenum chambers, (0) valve means controlling the flow of air into said and Pressure cfperated dampers F the dlscharge plenum ohambers, or? each fan, closing upon the shutting off of an in- (p) and must passageways leading through said divrdual fan and preventing the short circuiting of plenum chambers into said vacuum zone for withair through the 7. In a drying apparatus and in combination with a drying cylinder adapted to have (a) a fibrous web traveling thereabout, (b) a hood extending along said cylinder,

5. In a drying apparatus and in combination with a rotatable drying cylinder having a web traveling thereabout;

(a) a hood extending along said cylinder and having (12) an impingement plate conforming to and spaced closely adjacent said drying cylinder having (0) a plurality of air impingement nozzles leading therethrough,

(d) an air inlet leading into said hood,

(e) an exhaust outlet leading from said hood,

(f) damper means in said air inlet and said exhaust outlet operable to vary the flow of air into and from said hood,

(c) a pressure zone within said hood,

inner side of said impingement plate,

(i) a vplurality of Iiienum chambers spaced along the (j) anfihdiv-idual inlet'intb each plenum chambegl; v (k) selectively operable valve meanseontrolling the flow of air-"freon; said pressure zane 'thi oughlsaid inlets into said plenum chamber,

) and helical bafiies extendi g alohg the -inhe 1 side of said impingement plate in the general direction of travel of the webabout said eylinder d defiiii ng the side walls Of said plenum'Ychambers and blending the flow of'air through said air impingement n'oz z les along adjacent plenum Chambers.

" References Cited i 1,757,948 ,830 2,919Q495 V $9 ,1 5 24 3 74222 v r 3,012,335;

FOREIGN PATENTS V 

1. IN AN APPARATUS PARTICULARLY ADAPTED FOR DRYING A TRAVELING FIBROUS WEB IN THE MAKING OF PAPER; (A) A HOOD, (B) A PRESSURE ZONE WITHIN SAID HOOD, (C) A VACUUM ZONE WITHIN SAID HOOD, (D) AT LEAST ONE AIR FAN IN SAID HOOD ESTABLISHING SAID PRESSURE AND VACUUM ZONES, (E) AN AIR HEATER IN SAID PRESSURE ZONE, (F) A PLENUM IN COMMUNICATION WITH SAID PRESSURE ZONE HAVING A PLURALITY OF AIR IMPINGEMENT NOZZLES LEADING THEREFROM, (G) EXHAUST PASSAGEWAYS LEADING FROM THE TRAVELING WEB AND PASSING THROUGH SAID PLENUM AND HAVING COMMUNICATION WITH SAID VACUUM ZONE, (H) AND SPACED HELICAL BAFFLES EXTENDING ALONG SAID PLENUM AND DIVIDING SAID PLENUM INTO A PLURALITY OF PLENUM CHAMBERS HAVING HELICAL SIDE WALLS BLENDING THE AIR PASSING THROUGH ADJACENT PLENUM CHAMBERS ONTO THE TRAVELING WEB. 